[docs-beta] Map API lifecycle flags to style levels for docs beta (#2…

…6846)

## Summary & Motivation

Map the Preview, Beta and Superseded flags to warning level for
Docusaurus/docs beta styling. See comment
[here](#26821 (comment)).

docs/sphinx/_ext/sphinx-mdx-builder/sphinxcontrib/mdxbuilder/writers/mdx.py

@@ -972,6 +972,12 @@ def _flag_to_level(self, flag_type: str) -> str:
         level = "info"
         if flag_type == "experimental":
             level = "warning"
+        if flag_type == "preview":
+            level = "warning"
+        if flag_type == "beta":
+            level = "warning"
+        if flag_type == "superseded":
+            level = "warning"
         if flag_type == "deprecated":
             level = "danger"
         return level